From 915b53ab9963f30926e70334a98cdff5d51fd674 Mon Sep 17 00:00:00 2001
From: Quentin Grimonprez <quentingrim@yahoo.fr>
Date: Fri, 16 Oct 2020 11:26:47 +0200
Subject: [PATCH] Manage the case when lambda = 0 for Poisson and there are
 some missing intervals

---
 .../lib/Mixture/Simple/Poisson/Poisson.cpp    | 10 -------
 .../Simple/Poisson/PoissonStatistic.cpp       | 27 +++++++++++++------
 RMixtCompIO/DESCRIPTION                       |  4 +--
 RMixtCompIO/NEWS                              |  2 +-
 4 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/MixtComp/src/lib/Mixture/Simple/Poisson/Poisson.cpp b/MixtComp/src/lib/Mixture/Simple/Poisson/Poisson.cpp
index 85347f26fe..b558187d0e 100644
--- a/MixtComp/src/lib/Mixture/Simple/Poisson/Poisson.cpp
+++ b/MixtComp/src/lib/Mixture/Simple/Poisson/Poisson.cpp
@@ -64,16 +64,6 @@ std::string Poisson::mStep(const Vector<std::set<Index>>& classInd) {
 		}
 
 		param_(k) = sumClass / Real(classInd(k).size());
-
-		if (param_(k) < epsilon) {
-			warnLog +=
-					"Poisson variables must have a minimum mean of "
-							+ epsilonStr
-							+ " in each class. It is not the case in class: "
-							+ std::to_string(k)
-							+ "."
-							+ eol;
-		}
 	}
 
 	return warnLog;
diff --git a/MixtComp/src/lib/Mixture/Simple/Poisson/PoissonStatistic.cpp b/MixtComp/src/lib/Mixture/Simple/Poisson/PoissonStatistic.cpp
index 4b54c0b7d4..8dd5ac2112 100644
--- a/MixtComp/src/lib/Mixture/Simple/Poisson/PoissonStatistic.cpp
+++ b/MixtComp/src/lib/Mixture/Simple/Poisson/PoissonStatistic.cpp
@@ -53,9 +53,14 @@ Real PoissonStatistic::lpdf(int x, Real lambda) const {
 }
 
 Real PoissonStatistic::cdf(int x, Real lambda) const {
-	boost::math::poisson pois(lambda);
-	Real proba = boost::math::cdf(pois, x);
-	return proba;
+	if (0.0 < lambda) {
+		boost::math::poisson pois(lambda);
+		Real proba = boost::math::cdf(pois, x);
+
+		return proba;
+	} else {
+		return 1.0;
+	}
 }
 
 
@@ -103,11 +108,17 @@ int PoissonStatistic::quantile(Real lambda, Real p) const {
 	 * https://www.boost.org/doc/libs/1_69_0/libs/math/doc/html/math_toolkit/pol_tutorial/understand_dis_quant.html
 	 *
 	 */
-	boost::math::poisson_distribution<
-	            double,
-				boost::math::policies::policy<boost::math::policies::discrete_quantile<boost::math::policies::integer_round_up> > > pois(lambda);
-	int q = boost::math::quantile(pois, p);
-	return q;
+	if (0.0 < lambda)
+	{
+		boost::math::poisson_distribution<
+					double,
+					boost::math::policies::policy<boost::math::policies::discrete_quantile<boost::math::policies::integer_round_up> > > pois(lambda);
+		int q = boost::math::quantile(pois, p);
+		return q;
+	} else {
+		return 0.0;
+	}
+
 }
 
 int PoissonStatistic::quantileIB(Real lambda, int infBound, Real p) const {
diff --git a/RMixtCompIO/DESCRIPTION b/RMixtCompIO/DESCRIPTION
index 4bd48e00b1..d8c6097a55 100644
--- a/RMixtCompIO/DESCRIPTION
+++ b/RMixtCompIO/DESCRIPTION
@@ -2,7 +2,7 @@ Package: RMixtCompIO
 Type: Package
 Title: Mixture Models with Heterogeneous and (Partially) Missing Data
 Version: 4.0.6
-Date: 2020-10-15
+Date: 2020-10-16
 Authors@R: c(person("Vincent", "Kubicki", role = "aut"),
              person("Christophe", "Biernacki", role = "aut"),
              person("Quentin", "Grimonprez", role = c("aut", "cre"), email = "quentin.grimonprez@inria.fr"),
@@ -22,5 +22,5 @@ BugReports: https://github.com/modal-inria/MixtComp/issues
 Imports: Rcpp, doParallel, foreach
 Suggests: Rmixmod, blockcluster, testthat, RInside, xml2
 LinkingTo: Rcpp, RcppEigen, BH
-RoxygenNote: 7.1.0
+RoxygenNote: 7.1.1
 Encoding: UTF-8
diff --git a/RMixtCompIO/NEWS b/RMixtCompIO/NEWS
index ecc78a5e4f..41b757624b 100644
--- a/RMixtCompIO/NEWS
+++ b/RMixtCompIO/NEWS
@@ -2,7 +2,7 @@ v 4.0.6
 - catch error "XXX object does not exit."
 - rename some C++ classes and files
 - remove useless files
-- detect when the Poisson's parameter is estimated at 0
+- Manage the case when lambda = 0 for Poisson and there are some missing intervals  
 
 v4.0.5 2020-06-15
 - bug correction when z_class is in data but not in the model